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1.
Toxicol Mech Methods ; 34(2): 189-202, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37830174

RESUMO

Microextractions have been developed for the tricyclic antidepressants (TCAs) analysis in biological matrices, including dispersive liquid-liquid microextraction (DLLME). The proposed DLLME employed 490 µL of biological sample (whole blood or plasma), which were added 15 mg of NaCl, 10 µL of medazepam as internal standard (10 µg/mL) and 100 µL of 2 M NaOH. This mixture was homogenized by vortex (2800 rpm/10 s) and 400 µL of hexane (extractor solvent) with 600 µL of methanol (dispersing solvent) were added to the sample. After the vortex step (2800 rpm/5 s), an ultrasonic bath for 300 s was employed. Then, this content was centrifuged (10 min/10000 rpm), organic phase was collected and dried under air flow. After, 30 µL of the mobile phase was used for resuspension and 20 µL is injected into LC-DAD. This method was optimized and fully validated according to UNODC and SWGTOX guidelines, reaching limits of detection equivalent to analytical methodologies that employ mass spectrometry (MS). Also, it was applied in real cases involving suspected exposure to TCAs. So, the developed DLLME for the determination of TCAs in whole blood and plasma samples proved to be a simple, reliable, robust and reproducible method that can be used in toxicology and clinical laboratories.


Assuntos
Antidepressivos Tricíclicos , Microextração em Fase Líquida , Microextração em Fase Líquida/métodos , Cromatografia Líquida , Solventes , Espectrometria de Massas , Limite de Detecção
2.
Molecules ; 28(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36615250

RESUMO

Consumers increasingly prefer and seek functional beverages, which, given their characteristics, provide important bioactive compounds that help prevent and treat chronic diseases. Mead is a traditional fermented alcoholic beverage made from honey solution. The aging process of mead with oak chips is innovative and bestows functional characteristics to this beverage. Thus, in this study, we sought to develop and characterize a novel functional beverage by combining the health benefits of honey with the traditional aging process of alcoholic beverages in wood. Phenolic compounds, flavonoids, and antioxidant capacity were analyzed in mead using oak chips at different toasting levels and aged for 360 days. LC-ESI-QTOF-MS/MS was used to analyze the chemical profile of different meads. Over time, the aging process with oak chips showed a higher total phenolic and flavonoid content and antioxidant capacity. Eighteen compounds belonging to the classes of organic acids, phenolic acids, flavonoids, and tannins were identified in meads after 360 days. Our findings revealed that the addition of oak chips during aging contributed to p-coumaric, ellagic, abscisic, and chlorogenic acids, and naringenin, vanillin, and tiliroside significantly impacted the functional quality of mead.


Assuntos
Quercus , Vinho , Quercus/química , Espectrometria de Massas em Tandem , Antioxidantes/análise , Fenóis/química , Flavonoides/análise , Madeira/química , Vinho/análise
3.
Neotrop Entomol ; 50(4): 593-604, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33835382

RESUMO

Parasitoid wasps from the Aphelinidae family (Hymenoptera) are important control agents of Bemisia tabaci (Gennadius, 1889) cryptic species, both through reproduction and feeding processes. Identifying native parasitoid species within agricultural systems affected by Bemisia whitefly species is the first step to developing guidelines for the creation and release of biological control agents aiming at this highly damaging pest species complex. Taxonomic and phylogenetic analyses based on morphological and molecular characters, respectively, confirmed the occurrence of Encarsia formosa (Gahan, 1924) in greenhouse tomatoes from Santa Maria, Encarsia porteri (Mercet, 1928) in open-field soybean from Santa Maria, and Eretmocerus mundus Mercet, 1931 in greenhouse tomatoes from São José do Hortêncio, all within Rio Grande do Sul state (South Brazil). This is the first report of En. formosa, En. porteri and Er. mundus parasitising B. tabaci in South Brazil, and the first En. porteri partial mtCOI gene sequence being reported and characterised. The high temperature inside the tomato greenhouses can be a possible cause for the predominance of Er. mundus in São José do Hortêncio, and sex ratios in the surveyed populations point to female and male prevalence within Encarsia and Eretmocerus genera, respectively. The combined use of taxonomic and molecular characterisation highlights the importance of combining both morphological and molecular approaches in the assessment of previously unidentified whitefly parasitoids.


Assuntos
Glycine max , Hemípteros , Solanum lycopersicum , Vespas , Animais , Brasil , Hemípteros/parasitologia , Nigéria , Filogenia
4.
Bioprocess Biosyst Eng ; 43(1): 133-141, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31542822

RESUMO

Endophytic fungi have been highlight in the production of secondary metabolites with different bioactive properties, such as in the production of the antioxidant compounds. Therefore, the objective of this work was the extraction of the antioxidant compounds from the biomass of Diaporthe schini using supercritical carbon dioxide (CO2) without and with ethanol as cosolvent. The biomass was produced by submerged fermentation and the parameters evaluated in the extraction process were: pressure (150-250 bar), temperature (40-60 ºC) and cosolvent [biomass: cosolvent ratio, 1:0, 1:0.75 and 1:1.5 (w/v)]. Extraction yield, antioxidant activity and chemical composition of the extracts were determined. The highest extraction yield (3.24 wt.%) and the best antioxidant activity against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical (96.62%) were obtained at 40 ºC, 250 bar and biomass:cosolvent ratio of 1:1.5 (w/v). The chemical compounds 1,4-diaza-2,5-dioxo-3-isobutyl bicyclo[4.3.0]nonane and benzeneethanol identified in GC/MS could be responsible for the antioxidant activity found in this study.


Assuntos
Antioxidantes , Ascomicetos/química , Dióxido de Carbono/química , Etanol/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Solventes/química
5.
Food Res Int ; 125: 108645, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554039

RESUMO

The aim of this study was to develop and evaluate the physicochemical and antioxidant stability of nanoemulsions containing a Physalis peruviana calyx extract (CPp-NE) and free extracts under different storage conditions (7 and 25 °C) and with absence or incidence of light for 120 days. The calyx extracts were prepared with ethanol 60% and characterized for later preparation of the nanoemulsions by spontaneous emulsification. The formulations presented nanometric sizes, low polydispersity index, negative zeta potential, acid pH, rutin content (11 µg·mL-1), and encapsulation efficiency of 85%. Regarding the stability, the droplet size and PdI of the CPp-NE stored at refrigeration temperature in the dark, room temperature in the dark, and refrigeration temperature with light incidence were stable for 120 days and with no visible changes in the formulations. The antioxidant capacity was related to the reducing capacity, and the best results were found for nanoemulsions stored at room temperature and in absence of light. In addition, CPp-NE presented higher antioxidant and reducing capacity in relation to the free extracts.


Assuntos
Antioxidantes/química , Emulsões/síntese química , Flores/química , Nanopartículas/química , Physalis/química , Extratos Vegetais/química , Antioxidantes/análise , Fenômenos Químicos , Estabilidade de Medicamentos , Emulsões/química , Microscopia Eletrônica de Varredura , Rutina/análise
6.
J Biotechnol ; 294: 30-37, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30769000

RESUMO

The aim of this work was the production of bioactive metabolites by submerged fermentation from the fungus Diaporthe schini, followed by their extraction, separation and characterization. Different solvents (methanol, dichloromethane and hexane) were used for the extraction of metabolites from the fermentation broth and the extracts obtained were evaluated by in vitro antibacterial and antifungal activity. The separation and characterization of the extract from the hexane extraction was performed by column chromatography and GC-MS, respectively. The extracts had a great inhibitory action on the Gram-positive bacteria Staphylococcus epidermidis and Staphylococcus aureus, on the Gram-negative bacteria Enterobacter aerogenes and Klebsiella pneumoniae and on the fungus Candida krusei. The main metabolites produced were: 13-docosenamide, (Z)-; 2-hexadecene, 3,7,11,15-tetramethyl; 9-octadecenamide and 11-octadecenoic acid. Studies related to the antibacterial and antifungal activities of metabolites extracted from microorganisms are found in the literature. However, works about the identification of metabolites produced by submerged fermentation from Diaporthe schini were not found until the present moment. This work is an initial study where the conditions of the process can be optimized by looking for the production of a specific compound and can be a promising source for obtaining new drugs.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Ascomicetos/metabolismo , Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Ascomicetos/genética , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , DNA Fúngico/análise , Fermentação , Testes de Sensibilidade Microbiana , Solanum/microbiologia
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